Stereolithography (SLA) is a form of 3D printing technology used for creating parts in a layer by layer fashion using photochemical processes by which light causes the material to cure and the layers fused. Chuck Hull in 1984 applied for a patent on the process, which was granted in 1986. Stereolithography can be used to create prototypes for products in development, medical models, and computer hardware, as well as in many other applications.